Efficient analysis of a two-dimensional GTEM cell

The contribution deals with the efficient numerical evaluation and with a systematic study of the electromagnetic field within a two-dimensional semi-infinite tapered TEM waveguide partially filled with an arbitrary object. The investigation of this geometry is of interest for the judgement of the reliability of GTEM cells, which are widely used in EMC practice for susceptibility measurements with relatively small devices under test (DUT). The method is a combination of a modal analysis of the field within the empty parts of the cell and a method-of-moments analysis within the part which contains the DUT. The method can also be an interesting alternative to efficiently simulate other mostly homogeneous waveguides having an arbitrary inhomogeneous section. The numerical evaluation includes a comparison of the surface currents induced on a DUT located either within the cell or within the free space.